Strip feed mechanism

ABSTRACT

A strip feed mechanism for precisely feeding preselected lengths of a strip material, such as a paper used in photographic printing, in response to a predetermined signal. The drive includes positive stop mechanism for precise feeding of selected lengths, and adjustable means to permit feeding different lengths as desired. The length of feed is measured precisely, and the unit includes stop means that releases to stop the feeding mechanism at an exact position. The stop signal is dependent upon the length actually fed and is not affected by inertia or time lag in the starting of drive motors.

United States Patent Kallenberg [4 1 Jan. 18, 1972 [54] STRIP FEEDMECHANISM 3,352,468 11/1967 Shoemaker ..226/l34 X l t l K [72] nven orKar J allenberg, Minneapolis, Minn Primary Examiner Richard A. Schacher[73] Assignee: Electronic Systems Engineering Co., Cush- Anome -Dugger,Peterson, Johnson & Westman ing, Okla.

221 Filed: Jan. 26, 1970 [571 ABSTRACT [21] APPLNOJ 5,528 A strip feedmechanism for precisely feeding preselected lengths of a strip material,such as a paper used in photographic printing, in response to apredetermined signal. The

U-S. drive in ludes o itive stop mechanism for precise feeding of F. IdS h ..B65h 17/22 l t d l ths and adjustable means to permit feeding dif-1 l6 0 earc ..222266/ll35t]ll362, 141, I ferent lengths as desired. Thelength of feed is measured 3 133 precisely, and the unit includes stopmeans that releases to [56] Reterences Cited stop the feeding mechanismat an exact position. The stop UNITED STATES PATENTS Stansell ..226/l35X signal is dependent upon the length actually fed and is not affectedby inertia or time lag in the starting of drive motors.

15 Claims, 8 Drawing Figures PATENTEDJANIBIQYZ 3.635386 SHEET 2 OF 4FIG. 5

@ ll 1% all 197 INVENTOR A4421 1 xuzzvasz 4 frown/75 PATENTEUJAN IHYZEJ635386 SHEET 3 [IF 4 STRIP FEED MECHANISM BACKGROUND OF THE INVENTIONl Field of the Invention The present invention has relation tointermittent drive feed I mechanisms for feeding elongated material.

2. Prior Art In the feeding of strip material, such as used forphotographic printing machines, it has been known to utilize measuredfeeding devices. However, these usually employ some type of acontinuously running drive motor that is periodically engaged through aclutch mechanism to drive or feed rollers. In the usual case, some typeof mechanism electrically disengages the clutch mechanism used whenfeeding is complete. This type of device is shown in U.S. Pat. No.3,161,342, is-

sued to the present inventor. A fly back" arm is utilized in a thisdevice. While the device works satisfactorily, it becomes somewhatcomplex to manufacture.

A second type of device is shown in U.S. Pat. No. 3,460,732 also issuedto the present inventor. I-Iere small magnetic members are carried on aconstantly rotating wheel, and means are provided for releasing themagnetic members when the paper drive is tobe initiated or is initiatedat the same time the clutch mechanism to the paper drive is engaged. Themagnetic members then are used for breaking the circuit to the clutchdrive mechanism after they have traveled a preselected distance.

Again, the device shown in the U.S. Pat. No. 3,460,732 workssatisfactorily, but in certain instances the cost of manufacture becomesquite high, the device uses a number of small parts, and alsonecessitates the use of an electrically actuated clutch mechanismbetween the drive motor and the paper or strip drive wheels.

SUMMARY OF THE INVENTION The present invention relates to a feedingmechanism which is extremely simple in operation and does notnecessitate hav ing a constantly running drive motor or power means butstill gives precise feeding. The present invention as shown has a drivemeans that is initiated in response to release of a feeding latch andwhich then drives the feed. When the feed means has rotated apreselected amount, the latch is dropped to stop the feed and turn offthe drive motor or power means. The latch positively stops the feed atthe end of each cycle and resets the mechanism for the next cycle.

A latch wheel having cogs is used and carries settable stop pins thatengage a switch for breaking a circuit to stop the unit. The circuitbreaking switch is on a movable arm and can be adjusted so that theamount of rotation of the latch wheel for each feeding cycle can bechanged in increments, to change the length 'of material fed during eachcycle.

The unit is extremely simple to manufacture, low in cost, and utilizes aminimum number of parts. Additionally, the drive means for the feedmechanism does not have to be constantly running.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a fragmentary schematic sideelevational view of a strip feeding device including mechanism madeaccording to the present invention;

FIG. 2 is a fragmentary side elevational view of the exterior of thecase showing the means for adjusting strip-feed length;

FIG. 3 is a fragmentary top sectional view of thestrip'feed mechanismmade according to the present invention and taken as on line 3-3 in FIG.1;

FIG. 4 is an enlarged sectional view taken as on line 4-4 in FIG. 2'

]FIG. 5 is a sectional view taken as on line 5-5 in FIG. 4;

FIG. 6 is a fragmentary sectional view taken as on line 6-6 in FIG. 2;

FIG. 7 is a fragmentary sectional view taken as on line 7--7 in FIG. 6;and

FIG. 8 is a schematic diagram of an electrical circuit used forcontrolling the strip feed mechanism of the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENT A photographic printer 10, forexample, of the same type that is shown in U.S. Pat. No. 3,460,732, isshown schematically for-purposes of illustration. The unit includes ahousing 11 that forms a frame for the various components. The printingsection or work station is in the center, for example between lines 12.A roll 13 of photographic printing paper forming a strip supply ispositioned at one end of the housing, and a takeup roll 14 forphotographically printed paper or strip material is positioned at theother end of the machine 10. The strip feed mechanism is illustratedgenerally at 15 and is positioned adjacent the takeup roll. In otherwords, the feed mechanism 15 is on the opposite side of the printingstation 12 from the supply roll 13. The strip of paper being fedillustrated at 16, which extends across the printing station 12, remainsunder tension in the work station.

The supply roll 13 is mounted on a pair of idler rollers 17 and 18 whichare rotatably mounted on the frame, and the strip 16 passes from thissupply roll l3undemeath an inertia takeup roller 19, over a guide roller21, through the printing station 12, and then over a guide roller 22 onthe opposite side of the printing station. The paper strip 16 is pinchedagainst the outer surface of this guide roller 22 with a pair of spacedapart resilient pinch-drive rollers 23 mounted onto a common pinchroller shaft 24. The guide roller 22 is mounted onto a shaft thatextends across the frame, and is rotatably mounted thereon. The pinchroller shaft 24 is rotatably mounted onto brackets 25 that are springloaded with springs 26 fastened to the sides of the frame as at 27. Thepaper strip 16 passes from between the guide and pinch rollers, andunderneath a tension control roller 30. The tension control roller 30 ismounted on arms 31, that are pivoted and are spring loaded with a spring32 to put a controlled tension on the strip of material, and to cushionthe starting and stopping shocks when the paper is being fed. The papertakeup roll 14 is supported on an idler roller 33, and a takeup driveroller 34. The takeup roll is cradled on the rollers 33 and 34, whichare rotatably mounted on the frame. The roller 34 is driven with asprocket 35 through a chain 36 from a drive sprocket 37 on a papertakeup drive motor 38. The drive to the roller 34 is energized wheneverthe tension in strip 16 reduces to permit the arms 31 to drop. A switch38A having an actuator 38B is closed by an arm 31 when the feedingstarts, because the roll 30 and arms 31 drop. The motor 38 then startsto run, driving the takeup roll and it will continue to run until theroll 30 is lifted clearing the finger 38B. Usually this is after thefeed has stopped and the takeup roll tensions the strip 16 to cause roll30 and arms 31 to raise. The roller 30 and the roller 19 provide somecushion so that the inertia of the supply roll 13 does not cause thestrip to be torn when it is initially fed, and insures that the feedingwill be v made without having the paper strip tear.

The brackets 25 for mounting the pinch rollers permit the spring 26 topull the pinch roll shaft in direction to wedge the pinch roll againstthe guide roll 22, with the strip 16 between the roll surfaces. I

The strip 16 of paper or other material is fed intemiittently inresponse to predetermined signals. The feed drive occurs whenever alatch on the drive is released and a feed motor 40, is energized (seeFIG. 3). The motor 40 has an output shaft 41 driving a sprocket 42 thatin turn drives a chain 43. The chain 43 drives another sprocket thatdrives through a friction clutch 44 to drive a strip drive wheel 45. Theclutch 44 is a friction slip clutch having two metal plates with afriction plate between. The drive plate for the slip clutch is connectedto the drive sprocket and is rotatably mounted with respect to the drivewheel 45 on the shaft 46 for wheel 45. The second plate or inner plate(next to the wheel 45) is fixed or drivably attached with respect to thewheel. The wheel itself is drivably mounted on shaft 46. A spring isutilized for urging the first or outer plate of the friction clutch 44toward the second plate so there is force on the friction disc. Shaft 46extends across the housing and is mounted in suitable bearings on theframe. A second drive wheel 47 is also drivably mounted to the shaft 46on the opposite end thereof from wheel 45, adjacent the other sidewallof the frame or housing 11. It should be noted that the arms 31 aremounted on this shaft 46 and thus that the roller 30 pivots about theaxis of the shaft 46.

The drive or feed wheels 45 and 47 are used to drive the pinchfeedrollers 23. As can be seen, the shaft 24 at its ends adjacent thebrackets 25, carries short rollers 50. These rollers 50 are urgedagainst the surfaces of the feed wheels 45 and 47 under the tension fromthe springs 26. The brackets 25 are arranged so that the rollers 50 arejammed against the surfaces of the feed rolls 45 and 47 and at the sametime these pinch rolls 23 are forced against the surface of the roll 22.Thus the shaft carrying the rolls 23 and 50 is wedged under springpressure against the roll 22 and wheels 45 and 47. The spring pressurefrom the springs 26 insures that the pinch rolls bear against the paperstrip 16 to pinch the strip against the guide roller 22 and also insuresthat the rolls 50 are firmly urged against the surfaces of the wheels 45and 47 so that a positive drive results. The outer surfaces of wheels 45and 47 can be of a rough surface and rolls 50 may be of high frictioncoefficient material.

The shaft 46 extends through a sidewall 51 of the housing 11 (see FIG.4), and a latch ratchet wheel assembly 52 is drivably mounted onto theouter end of the shaft. The latch wheel assembly 52 actually is made upin two segments, and is used for positively controlling the amount offeed of the strip 16. A desired length of strip to be fed can bepreselected. The latch wheel assembly 52 as shown, has a first cogratchet wheel section 53 which comprises a latch section. As shown, theouter periphery of the ratchet wheel 53 has a plurality of receptacles54 defining latch receptacles. A second portion of the wheel assembly 52comprises a housing 55 which houses a plurality of axially extendingpins 56. There is one pin 56 aligned with each of the receptacles 54.The pins 56 are detented pins. Each pin has a pair of annular recessesaround its periphery. A garter spring 57 is placed in a provided groovearound the periphery of the wheel and partially enters receptacles forthe pins 56 so that the spring will engage one or the other of theannular recesses on each of the pins 56. The spring 57 thus will retainthe pins 56 either retracted as shown at the bottom position of thewheel in FIG. 4 or in a set position as shown at the top of the wheel inFIG. 4. The pins 56 are moved from this retracted position wherein theyare flush with the side surface 60 of the latch wheel, to their setposition where they protrude outwardly beyond this side surface 60 eachtime the latch is used to stop the feeding.

The strip feed device has a latch mechanism illustrated generally at 61adjacent the bottom of the latch wheel assembly, and operating inconjunction with the latch ratchet wheel portion of the latch wheelassembly to positively stop the feeding of the strip 16 at a preselectedposition. The latch mechanism includes a latch dog 62 that is mounted ina slot in a bracket 63 so that it will pivot with respect to thisbracket (see FIGS. 4, 6 and 7) and also will slide in and out (in axialdirection of the shaft 46) as shown in FlGS. 4 and 7 in response tomovement of a rotary-type solenoid 64. The bracket 63 and solenoid 64are mounted to a bracket 81 that is fastened to the wall 51. Thesolenoid 64 has a rotor 78 carrying an output pin 65 that rotatesslightly about a central axis when the solenoid is energized. Thesolenoid is shown in energized position in FIG. 4. The dotted lineposition of pin 65 shows the solenoid in its relaxed position. Thesolenoid 64 is spring loaded to its relaxed position.

The latch dog 62 extends laterally from the solenoid through providedopenings in wall 51 and has cutout portions in the center part thereof.The latch dog 62 has a slot defined therein which rides over aguide-stop bar 66 attached to the sidewall 51 of the housing,.and asshown in H6. where the latch wheel is partially broken away, the guidebar 66 has an upright end portion 67 that acts as a stop to interceptmovement of the latch dog along this guide bar in direction as indicatedby the arrow 71 after the latch has moved to a preselected position inthis direction. The latch dog has a cutout portion 72, which has abottom edge positioned to clear the periphery of the cogged wheel. Therecess also forms a shoulder 73 aligned with the inner side surface ofthe cogged wheel 53, and of size so that it will slide into thereceptacles 54 and will hold the latch wheel from turning because thecogs will stop against the latch dog when the dog is in its relaxedposition.

In addition, the latch dog has an upright end member 74 with a bent overtab which is positioned to engage the pin 56 aligned with orcorresponding to the receptacle 54 which the latch dog enters. When thelatch dog 62 is moved to its at rest" or latched position, the endmember 74 will push the corresponding one of .the pins 56 from itsneutral position to its set position protruding outwardly beyond thesurface 60. This is done at the same time that the shoulder 73 entersone of the receptacles 54 to positively stop the wheel 53 when the latchdog collides against the upright member 67 to positively stop the coggedwheel at this rotational position and thus stop the paper feed. Thelatch dog is also spring loaded to pivot in bracket 63 in directionopposite that from indicated by the arrow 71 through the use of anelongated pin or bolt 75 which is attached to the latch dog, and aspring 76 that in turn is attached to the bolt 75 and to a pin 77 whichis fixed to a bracket 81 attached to wall 51. The spring 76 will insurethat the latch dog 62 pivots so that it is back and set for stopping thelatch wheel. The latch will slide in axial direction along pin 65 ashort distance.

ln addition, the latch dog includes a switch actuating lug 79 extendingdownwardly therefrom and adapted to engage and actuate a switch 80mounted onto bracket 81. The bracket 81 is U" shaped, as shown.

The bracket 81 has an upright wall and is used for mounting a selectassembly for selecting and controlling the lengths of paper to be fed.The select assembly includes a shaft 85 rotatably mounted in the uprightwall of bracket 81 and a selector wheel 86 and control knob 87 are bothdrivably mounted onto the shaft. The shaft 85 can be slid in axialdirection as well as rotated. A hub 88 is mounted onto the sidewall ofthe bracket 81, and the shaft 85 is rotatably mounted therein. A controllug 91 is drivably mounted on the shaft 85 on the inner end thereof anda spring 92 is positioned over the hub 88, and between the innersurfaces of the upright wall of bracket 81 and the lug so that the knoband shaft 85 are urged in direction as indicated by the arrow 92A. Thewheel 86 has a plurality of holes therein, as can perhaps best be seenin FIG. 2, and the holes are of size to fit over a small stud 93 that isfixed to the wall of bracket 81. By pulling the knob in directionopposite from arrow 92A against the action of the spring 88, the wheel86 can be released from the stud 93 and rotated to a desired position.

At the same time, therefore, the lug 91 will be rotated. As shown, thelug 91 has an arm 94 drivably mounted thereon and the arm in turncarries a switch 95 thereon. A switch actuator wheel 96 is rotatablymounted about the axis of a pin 97 mounted on a support plate 100 whichis mounted on the outer end of arm 94. The switch actuator wheel is astar shaped wheel, as perhaps can be best seen in FIG. 3, and a switchactuator finger 101 is positioned so that it will be moved by the lugson the star wheel when the wheel rotates. In other words, when thefinger is in a central position between the lugs and the star wheel, theswitch will be in its open position, and when the wheel rotates the lugsmove the finger to actuate the switch 95. The star wheel actuallyrotates an amount equal to one lug spacing each time it is actuated, sothat the switch 95 will be momentarily actuated and then released again.

The plate 100 also carries a pin return guide block 106 mounted thereon.The guide block is made of material having a low coefficient of frictionand has a rounded end portion that engages a set pin as the wheel turnspast the plate and pushes it back to its retracted or neutral position.Thus. only one pin will be set, and it is retracted as soon as it hasoperated switch 95 to stop strip feed.

The strip drive unit is controlled through a holding relay. When amomentary electrical signal is given for the unit to feed, for exampleby depression of a pushbutton 107 momentarily, the signal energizes aholding relay 105 which "looks on" through its own contacts to powercoming through switch 95, and operates the solenoid 64. The solenoid 64goes to its by the block 106 when the wheel 52 moves past the block.

energized position (solid lines in-FlG. 4) and releases the latchshoulder 73 from the receptacle 54 of the wheel 53. The shoulder 73 iswithdrawn from the receptacle 54 in which it was placed. it should benoted that the pin 56 corresponding to this receptacle 54 holding thelatch dog -will have been moved to its set position when the latch doghad entered that receptacle, so that the pin 56 corresponding to thatreceptacle will be protruding beyond the outersurface 60 of the wheel.When the latch dog is moved to its wheel release position (the solenoidis energized), the lug 79 will move away from the switch 80, actuatingthe switch and then in turn causing the motor 40 to be energized. Themotor 40 has a small brake 102 thereon acting against a wheel 103 thatis directly connected to the shaft of the motor. The brake is solenoidoperated and at the same time that the-motor 'is energized, the brake102 will be released by withdrawing the brake shoe 104 from the wheel103 and permitting the motor 40 to start. The motor will start, drivingthe chain 43 and in turn driving through the friction clutch 44 to thewheel 45, shaft 46 and wheel 47. These wheels 45 and 47 will in turndrive against the rolls 50, driving the pinch rollers through the shaft24 and positively feeding paper. Because the latch dog shoulder 73 hasbeen withdrawn, feeding can occur.

The control signal is momentary, but the power to the solenoid iscarried through a holding relay 105 that in turn is locked on througharm switch 95. The unit will thus continue to drive, until the wheel 53hasrotated a sufficient amount so that the protruding pin 56 (set by thelatch dog at the end of the previous cycle) will engage one of the lugson the star control wheel 96 causing the switch control wheel to rotateabout its upright axis one space, thereby opening the switch 95. Openingswitch 95 breaks the holding circuit to the holding relay 105 and thusto solenoid 64. When the circuit is broken, the latch dog 62 will bepulled back into a preselected one of the receptacles 54 so that theshoulder 73 will enter a receptacle 54 on the cog wheel, and the tab orlug 79 will open switch 00, stopping motor 40 and setting the brake onthe motor 40. At the same time, the pin 56 corresponding to thisreceptacle 54 will be pushed out into its set position. When the latchdog is released, spring 76 acts to pull the latch toward rotor 78 totake up any pivoting movement of the latch and move it in directionopposite from arrow 71 to the solid line position of FIG. 7. Then thecog wheel can coast until the latch dog comes to the stop against theupright member 67. The latch dog thus will move a short distance indirection indicated by arrow 71 after the dog has entered areceptacle54. The feed will be positively stopped when the latch dogstops against this upright member 67. A precise length of strip materialthus has been fed. The feed motor 40 is deenergized. The take up motor38 will continue to run until the tension in strip 16 lifts roller 30and arms 31 from the switch actuator 38B thereby opening switch 38A andstopping the motor 38.

However, the coasting or inertia of the feed mechanism will continue tomove the wheel 52 so that the latch dog will positively come against itsstop member 67 in a precise preselected position. lf a different lengthof strip is to be fed, the knob and control wheel 86 are reset so that adifi'erent hole is positioned with the stud 93. This will move theentire arm 94, switch 95 and its control wheel 96 to a different angularposition meaning that the control wheel assembly will have to rotate adifferent number of degrees beforethe set pin '56 engages the star wheel96, opens switch 95 and breaks the cir- The term strip material" hasbeen used, and of course, this includes sheets, rods or other elongatedforms of material. Further the principles are not limited merely torotary feeding mechanisms, but can be employed with linear feedingdevices.

1 claim:

1. A mechanism for feeding preselected lengths of material comprisingfeed means for said material including power means and latch means, saidlatch means including an element movable between a normalfeed-permitting and a feed posi-v tion, control means to hold saidelement in said feed-permitting position in response to a predeterminedsignal, said element including an actuator, means controlled by saidactuator to energize said power means when said element moves tofeed-stopping feed-permitting position, and disabling means to disablesaid control means when said feed means has fed a preselected amount ofstrip material.

2. A mechanism for feeding preselected lengths of elongated materialcomprising a supply of material, elongated feed means for removing saidmaterial from said supply, and drive means for said feed means, saidfeed means including latch means, said latch means having a latchratchet movable with said feed means, and a latch dog, said latch dogbeing movable between a first normal position engaging said latchratchet thereby preventing movement of said feed means to a secondposition spaced from said latch ratchet, means to urge said latchratchet to its first position, control means activated by said latch dogin its second position to energize said drive means, means to move saidlatch dog to said second position and retain said latch dog in saidsecond position in response to a predetermined signal, and disablingmeans to disable said means holding said latch dog in its secondposition after said feed means has fed a preselected amount of materialthereby to deenergize said drive means.

3. The combination as specified in claim 2 wherein said drive meansincludes a rotary element and said latch ratchet comprises a wheelmember having a plurality of receptacles therein, said latch dogentering one of said receptacles whenever said dog moves to its firstposition.

4. The mechanism of claim 3 wherein said disabling means comprises meanspositioned adjacent the path of movement of said latch ratchet, andspaced from said latch dog, a plurality of settable members carried bysaid latch ratchet, one corresponding to each of the holding positionsof said latch dog, said settable members being movable from a retractedposition to a set position, means on said latch dog to set a settablepin corresponding to the position on the latch ratchet of said latch dogwhen said latch dog moves to its first position, said members beingpositioned to actuate said disabling means when said members are in saidset position and are moved past said disabling means by said latchratchet during operation of said feed means, and means to move said pinsto their neutral positions when they have passed said switch.

5. The combination as specified in claim 4 and means mounting a portionof said disabling means for movement adjacent the path of travel of saidlatch ratchet with respect to said latch dog, and stop means forselectively holding said portion in a desired position adjacent the pathof travel of said latch ratchet.

6. The combination as specified in claim 3 wherein said latch dog moveslaterally from said wheel member to be withdrawn from a receptacle assaid latch dog is moved to said second position, and said latch ratchetalso is moved generally in opposite direction of movement of said wheelmember as said latch dog moves to said second position after said latchdog has been withdrawn from said receptacles, said disabling meansreleasing said latch dog from its second position and said latch dogfirst moving laterally to engage a receptacle in said wheel member anddeenergize said power means prior to reaching said first position, andsaid latch dog moving with said wheel member under inertial forces tosaid first position after said power means has been deenergized bymovement of said latch dog away from its second position, and positivestop means engaging said latch dog in position in a receptacle in saidwheel to prevent movement of said wheel when said dog has reached itsfirst position.

7. The combination as specified in claim 3 wherein said means to holdsaid latch dog in its second position comprises a rotary solenoid havingan axis substantially normal to axis of movement of said wheel member, apin mounted on and driven in rotational direction by said rotarysolenoid and spaced from the axis of said solenoid, said latch dog beingmounted for movement on said pin in direction of the axis of rotation ofsaid'solenoid also being moved with said pin laterally to the plane ofmovement of said wheel when said solenoid is operated to withdraw saiddog from a receptacle in said wheel when said latch dog is first movedtoward said second position, and bias means to slide said latch dog onsaid pin in opposite direction from direction of movement of said wheelmember after said latch dog has moved laterally as said latch dog movesto its second position, said latch dog first moving laterally to engageareceptacle in said wheel member and deenergizing said power means andsubsequently moving along said pin under influence of said wheel memberto said latch dog first position after said disabling means hasoperated.

8. The combination as specified in claim 2 'wherein said means forholding said latch dog in its second position comprises solenoid meansoperated in response to an electrical signal.

9. The combination as specified in claim 2, and means to mount saidlatch dog for limited movement with said latch ratchet as said latch dogmoves from said second position toward said first position, said latchdog first moving to engage said latch ratchet after disabling means hasbeen activated whereby said latch ratchet can coast with said latch dogengaged in said latch ratchet until the latch dog reaches its firstposition.

10. A mechanism for feeding preselected lengths of strip materialcomprising a supply of material in strip form, feed means for removingsaid strip material from said supply, and drive means for said feedmeans including a drive motor and a rotatable element, latch means forsaid rotatable element, said latch means including a latch ratchetcomprising a wheel member having a plurality of receptacles definedtherein and a latch dog, means to move said latch dog between a firstposition engaging one of the receptacles of said latch ratchet therebypreventing movement of said rotatable element to a second positionspaced from said latch ratchet, means to hold said latch dog spaced fromsaid latch ratchet in response to a predetermined signal, and disablingmeans to disable said means holding said latch dog spaced from saidlatch ratchet after said feed means has traveled a preselected amount,said disabling means comprising electrical circuit holding means switchmeans positioned adjacent the path of movement of said wheel fordisabling said circuit holding means, a plurality of pins carried bysaid wheel member, one pin corresponding to each of the receptacles insaid wheel member, said pins beingmovable from a retracted position to aset position, means on said latch dog to set a pin corresponding to thereceptacle said latch dog enters when said latch dog moves to its firstposition, said pins being positioned to actuate said switch means when apin is in said set position and a pin in set position is moved by saidwheel member past said switch, and means to move each set pin to itsneutral position after said set pin has moved past said switch.

11. The combination as specified in claim 10, means mounting said switchmeans for movement about the axis of rotation of said wheel, and stopmeans for selectively holding said switch means in an angular positionabout said axis of movement of said wheel.

12. The combination as specified in claim 10 and means including switchmeans actuated by movement of said latch dog to its second position toenergize said motor for said feed means.

13. The combination as specified in claim 12 and friction clutch meansbetween said motor and said drive means.

14. The combination as specified in claim 12 wherein said means forholding said latch dog in its second position comprises solenoid meansoperated in response to an electrical signal.

15. The combination as specified in claim 14 and spring means urgingsaid latch dog toward its first position, said solenoid means overcomingthe force of said spring means.

@2 3 UNITED STATES PATENT oEETcE CERTIFICATE 0F CORRECTWN Patent No. 3$3 5,386 Dated January 18, 1972 Karl J. Kal'lenberg Inventor(s) It iscertified that error appears in the above-identified patent and thatsaid Letters Patent are hereby corrected as shown below:

"* Column 8, Line 33 (clash 13, line 1) "Claim 12 Column 8, Line 35(Claim 14, line 1) should be--Cl-aim lO--; "Claim 12'' should be--ClaimlO--.

Signed and sealed this 26th day of September 1972.

(SEAL) Attest:

EDWARD M.FLETCHER,JR. ROBERT GOTTSCHALK Attesting Officer Commissionerof Patents

1. A mechanism for feeding preselected lengths of material comprisingfeed means for said material including power means and latch means, saidlatch means including an element movable between a normalfeed-permitting and a feed position, control means to hold said elementin said feed-permitting position in response to a predetermined signal,said element including an actuator, means controlled by said actuator toenergize said power means when said element moves to feed-stoppingfeedpermitting position, and disabling means to disable said controlmeans when said feed means has fed a preselected amount of stripmaterial.
 2. A mechanism for feeding preselected lengths of elongatedmaterial comprising a supply of material, elongated feed means forremoving said material from said supply, and drive means for said feedmeans, said feed means including latch means, said latch means having alatch ratchet movable with said feed means, and a latch dog, said latchdog being movable between a first normal position engaging said latchratchet thereby preventing movement of said feed means to a secondposition spaced from said latch ratchet, means to urge said latchratchet to its first position, control means activated by said latch dogin its second position to energize said drive means, means to move saidlatch dog to said second position and retain said latch dog in saidsecond position in response to a predeterminEd signal, and disablingmeans to disable said means holding said latch dog in its secondposition after said feed means has fed a preselected amount of materialthereby to deenergize said drive means.
 3. The combination as specifiedin claim 2 wherein said drive means includes a rotary element and saidlatch ratchet comprises a wheel member having a plurality of receptaclestherein, said latch dog entering one of said receptacles whenever saiddog moves to its first position.
 4. The mechanism of claim 3 whereinsaid disabling means comprises means positioned adjacent the path ofmovement of said latch ratchet, and spaced from said latch dog, aplurality of settable members carried by said latch ratchet, onecorresponding to each of the holding positions of said latch dog, saidsettable members being movable from a retracted position to a setposition, means on said latch dog to set a settable pin corresponding tothe position on the latch ratchet of said latch dog when said latch dogmoves to its first position, said members being positioned to actuatesaid disabling means when said members are in said set position and aremoved past said disabling means by said latch ratchet during operationof said feed means, and means to move said pins to their neutralpositions when they have passed said switch.
 5. The combination asspecified in claim 4 and means mounting a portion of said disablingmeans for movement adjacent the path of travel of said latch ratchetwith respect to said latch dog, and stop means for selectively holdingsaid portion in a desired position adjacent the path of travel of saidlatch ratchet.
 6. The combination as specified in claim 3 wherein saidlatch dog moves laterally from said wheel member to be withdrawn from areceptacle as said latch dog is moved to said second position, and saidlatch ratchet also is moved generally in opposite direction of movementof said wheel member as said latch dog moves to said second positionafter said latch dog has been withdrawn from said receptacles, saiddisabling means releasing said latch dog from its second position andsaid latch dog first moving laterally to engage a receptacle in saidwheel member and deenergize said power means prior to reaching saidfirst position, and said latch dog moving with said wheel member underinertial forces to said first position after said power means has beendeenergized by movement of said latch dog away from its second position,and positive stop means engaging said latch dog in position in areceptacle in said wheel to prevent movement of said wheel when said doghas reached its first position.
 7. The combination as specified in claim3 wherein said means to hold said latch dog in its second positioncomprises a rotary solenoid having an axis substantially normal to axisof movement of said wheel member, a pin mounted on and driven inrotational direction by said rotary solenoid and spaced from the axis ofsaid solenoid, said latch dog being mounted for movement on said pin indirection of the axis of rotation of said solenoid also being moved withsaid pin laterally to the plane of movement of said wheel when saidsolenoid is operated to withdraw said dog from a receptacle in saidwheel when said latch dog is first moved toward said second position,and bias means to slide said latch dog on said pin in opposite directionfrom direction of movement of said wheel member after said latch dog hasmoved laterally as said latch dog moves to its second position, saidlatch dog first moving laterally to engage a receptacle in said wheelmember and deenergizing said power means and subsequently moving alongsaid pin under influence of said wheel member to said latch dog firstposition after said disabling means has operated.
 8. The combination asspecified in claim 2 wherein said means for holding said latch dog inits second position comprises solenoid means operated in response to anelectrical signal.
 9. The combination as specified in claim 2, and meansto mount said latch dog for limited movement with said latch ratchet assaid latch dog moves from said second position toward said firstposition, said latch dog first moving to engage said latch ratchet afterdisabling means has been activated whereby said latch ratchet can coastwith said latch dog engaged in said latch ratchet until the latch dogreaches its first position.
 10. A mechanism for feeding preselectedlengths of strip material comprising a supply of material in strip form,feed means for removing said strip material from said supply, and drivemeans for said feed means including a drive motor and a rotatableelement, latch means for said rotatable element, said latch meansincluding a latch ratchet comprising a wheel member having a pluralityof receptacles defined therein and a latch dog, means to move said latchdog between a first position engaging one of the receptacles of saidlatch ratchet thereby preventing movement of said rotatable element to asecond position spaced from said latch ratchet, means to hold said latchdog spaced from said latch ratchet in response to a predeterminedsignal, and disabling means to disable said means holding said latch dogspaced from said latch ratchet after said feed means has traveled apreselected amount, said disabling means comprising electrical circuitholding means, switch means positioned adjacent the path of movement ofsaid wheel for disabling said circuit holding means, a plurality of pinscarried by said wheel member, one pin corresponding to each of thereceptacles in said wheel member, said pins being movable from aretracted position to a set position, means on said latch dog to set apin corresponding to the receptacle said latch dog enters when saidlatch dog moves to its first position, said pins being positioned toactuate said switch means when a pin is in said set position and a pinin set position is moved by said wheel member past said switch, andmeans to move each set pin to its neutral position after said set pinhas moved past said switch.
 11. The combination as specified in claim10, means mounting said switch means for movement about the axis ofrotation of said wheel, and stop means for selectively holding saidswitch means in an angular position about said axis of movement of saidwheel.
 12. The combination as specified in claim 10 and means includingswitch means actuated by movement of said latch dog to its secondposition to energize said motor for said feed means.
 13. The combinationas specified in claim 12 and friction clutch means between said motorand said drive means.
 14. The combination as specified in claim 12wherein said means for holding said latch dog in its second positioncomprises solenoid means operated in response to an electrical signal.15. The combination as specified in claim 14 and spring means urgingsaid latch dog toward its first position, said solenoid means overcomingthe force of said spring means.